Process for removing water from wet lengths of fabrics



United States Patent 3,501,788 PROCESS FOR REMOVING WATER FROM WET LENGTHS 0F FABRICS Alfred Schraud, Hambnrg-Wandsbek, Germany, assignor to Artos Dr. Ing. Meier-Windhorst K.G., Hamburg, Germany, a corporation of Germany N0 Drawing. Filed Dec. 15, 1967, Ser. No. 690,801

Int. Cl. 1306f 51/00 US. Cl. 8-158 1 Claim ABSTRACT OF THE DISCLOSURE The process for removing water from wet lengths of material, particularly after washing processes, is charac terized in that, at the end of a normal known washing process in washing sections which follow each other, the length of material in the last washing section is treated at the highest possible temperature, preferably boiling temperature, is then subjected to a squeezing process with preferably average squeezing output while retaining this temperature to the greatest possible extent and subjected to subsequent evaporation.

This invention relates to a process of removing water continuously from wet lengths of fabrics, particularly at the end of washing processes.

The usual procedure is to utilize batch processes and to remove as much water as possible from wet treated lengths of material after the treatment and then to allow them to rest in as cool condition as possible. This is required since it is either necessary to save energy for the following drying process, or in case of a following wet-in-wet treatment, such as impregnation, dyeing or bleaching, the length of material must be in a condition which permits it to well absorb the new treating bath. The resting in as cool condition as possible is used to prevent the drying of the edges in a rolled up or folded lengths of material.

For these reasons, in the known treatments the last washing section is usually not heated and the last squeezing apparatus is set for the highest possible output. This has the drawback that, due to lack of heating, the washing output of the last section is very low. The squeezing apparatus required to operate with the highest output is very expensive and operates with high costs.

An object of the present invention is to eliminate these drawbacks.

These drawbacks can be avoided by heating the last Washing section close to the boiling temperature, while for removing water an inexpensive and cheaply operating squeezing device of average output is used, whereby after the squeezing the material is cooled either in an air flow or by means of a so-called cooling blower, while using the eifect of subsequent evaporation, whereby it is advantageous to heat the air close to the air flow or at the outlet of the cooling blower to the extent that it does not drop below its dew point when contacting the material.

The following example of the process of the present invention is given by way of exemplification only.

EXAMPLE A process for removing water from wet lengths of materials, particularly after washing procedures, is characterized in that, at the end of a normal washing procedure in washing sections which follow each other in a manner known per se, the length of material is treated in the last washing section at the highest possible temperature, preferably boiling temperature, and then while keeping this temperature, is subjected to a squeezing process with preferably average squeeze output and is subjected to subsequent evaporation procedure. The evaporation can be strengthened by blowing-in upon the material. It was found advantageous to carry out the cooling by supplying warmed air to the material so that energy released during the. cooling of the material will be utilized to the greatest possible extent for removing water therefrom. Obviously cooling can also be carried out by passing the material overcooled drums; this, however, results in a much smaller removal of water. To make water removal as eflFective as possible, the cooling air should have the smallest possible moisture content.

The steps of this process provide a series of substantial advantages as compared to prior art processes. The last washing section is provided with its best possible washing output and the water removal of the squeezing section is increased, as is known, by about 12% moisture degrees, so that at this location alone a cheaper squeezing device produces a substantially better water removal than a. high output squeezing apparatus. The subsequent evaporation, namely, the conversion of the heat content of the material and of the liquid contained therein, produces a further desiccation of 10 to 15% moisture degrees following the corresponding laws of physics. This last effect depends upon the amount of thermic energy which was convectively removed and which theoretically would supply about 17% moisture degrees after subsequent evaporation. It is possible to diminish the loss when air which is applied to the material during evaporation has the smallest possible relative degree of humidity; this can be attained either by drying or by heating.

Obviously it is not necessary for carrying out the process of the present invention to replace the heretofore usual high output squeezing apparatus by a cheaper squeezing device, but there are advantages in doing so since the eflectiveness of a high output squeezing apparatus which is bad as is, becomes still worse by combination with subsequent evaporation, whereby the costs of the cooling blower or for producing the air flow are completely or partially compensated by the cheaper final squeezing device.

The cooling air can be heated merely to about 60 C. This can be carried out by means of a heat exchanger heated by the outflow water of the washing machine, so that no additional energy is required.

It is apparent that the above described example is capable of many variations and modifications within the scope of the present invention.

What is claimed is:

1. A process for continuously removing water from a wet length of material comprising continuously subjecting the material to washing in several stages, the washing in the last stage being carried out at the boiling temperature of the washing liquid, then squeezing the material while maintaining said high temperature, and then subjecting to subsequent water removal by impinging thereupon a continuous flow of hot air at a temperature of approximately 60 C.

References Cited UNITED STATES PATENTS 644,498 2/1900 Cook 68-9 X WILLIAM 1. PRICE, Primary Examiner US. Cl. X.R. 68-20, 22 

